Increasing damage is being caused by mites in house dust and this is attributable to various factors including the recent tendency of ensuring insulation of the residential environment from the ambient atmosphere and the westernization of the life style of Japanese people. While many mites are problematic, Dermatophagoides are worth particular attention since they are held as the most important allergen for infantile asthma and a topic dermatitis. Methods for controlling mites in house dust range from massive ones such as installing wooden floors, removal sofas and drying tatami mats, rugs and carpets to the treatment with chemicals which is relatively easy to perform. Conventionally applied chemicals include fenthion, fenitrothion, DDVP and permethrin, as well as 3-phenoxybenzyl chrysanthemate which is used as an active ingredient in the present invention. Another control means that is gaining popularity these days is the use of mite-proof bed spreads made of microfine fibers. However, the effectiveness of these conventional mite control means is not completely reliable since they are influenced by various factors of the residential environment. To ensure effective mite control, a certain ancillary means is necessary for checking the effectiveness of the treatment applied or determining whether it is truly necessary to perform the mite control or deciding upon the area that needs intensive control. In fact, however, the very small size of mites makes it generally difficult to know whether a certain area is infested with mites. Conventionally, the existence or density of mites in a house has been detected by the color reaction between the mite residue in house dust and an aromatic diazo compound (Japanese Patent Public Disclosure No. 135844/1985), or using a compound that develops a color upon reaction with the body fluid of a mite (Japanese Patent Public Disclosure No. 83624/1994) or by using a monoclonal antibody (Japanese Patent Public Disclosure No. 207892/1993). However, these and other conventional methods of mite control have various problems such as reacting not only with a living mite but also with a dead mite, reacting with both mites and other organisms, requiring special equipment or involving cumbersome operations. Thus, there has been no convenient and positive method that allows for specific reaction with living mites.